1.2 - Memory & Storage

Question 1

What are the two types of primary storage?

Answer 1

• Random Access Memory (RAM)
• Read Only Memory (ROM)

Question 2

What does Random Access Memory (RAM) do?

Answer 2

Holds open programs and data until the CPU is turned off (it is volatile)

Question 3

Is RAM volatile or non-volatile?

Answer 3

Volatile

Question 4

What does Read Only Memory (ROM) do?

Answer 4

Contains the bootstrap loader / Bios / loads the OS from storage into RAM

Question 5

Is ROM volatile or non-volatile?

Answer 5

Non-volatile

Question 6

What is secondary storage?

Answer 6

Permanent, non-volatile, long term storage for programs and data

Question 7

What is virtual memory?

Answer 7

When RAM is full, part of the secondary storage may be used like RAM, storing open programs

Question 8

What are the three types of secondary storage?

Answer 8

• Magnetic
• Optical
• Solid state

Question 9

How does magnetic storage work?

Answer 9

A read/write head moves nanometres above the disk platter and uses the magnetic field of the platter to read or edit data

Question 10

What is an example of a magnetic storage device?

Answer 10

Hard Disk Drive (HDD)

Question 11

What are the advantages and disadvantages of magnetic storage?

Answer 11

Advantages:
- Large capacity
- Cheap cost per GB
- Reliable

Disadvantages:
- Not durable
- Slower access speed

Question 12

How does optical storage work?

Answer 12

Uses a laser to project beams of light onto a spinning disc

Question 13

What are examples of optical storage devices?

Answer 13

CDs, DVDs and Blu-Ray

Question 14

What are the advantages and disadvantages of optical storage?

Answer 14

Advantages:
- Portable
- Cheap
- Reliable

Disadvantages:
- Not durable
- Low capacity per disc
- Slowest access speed

Question 15

How does solid state storage work?

Answer 15

Electronic circuitry

Question 16

What is are examples of solid state storage device?

Answer 16

Solid State Drives (SSD), USB flash drives and memory cards

Question 17

What are the advantages and disadvantages of solid state storage?

Answer 17

Advantages:
- Fastest access speed
- Durable
- Portable
- High capacity

Disadvantage
- Most expensive per MB

Question 18

What is a character set?

Answer 18

A table that assigns each character a unique binary value

Question 19

How many bits does ASCII have to represent a character?

Answer 19

8 bits per character

Question 20

How many characters does ASCII have room to represent?

Answer 20

2^8 = 256

Question 21

What can Unicode do?

Answer 21

Represent thousands of characters

Question 22

What is image resolution?

Answer 22

Number of pixels

Question 23

What is colour depth?

Answer 23

Number of bits per pixel used to represent colours

Question 24

What are examples of metadata?

Answer 24

Height, width, colour depth, file type, geolocation, camera model, date taken, etc.

Question 25

What is sample rate?

Answer 25

Number of samples per second (Hz)

Question 26

What is bit depth?

Answer 26

Number of bits used to represent a sample

Question 27

What is compression and why is it used?

Answer 27

Reducing file size to take up less storage space and have shorter transmission times

Question 28

What does lossy compression do?

Answer 28

Deletes parts of the file permanently

Question 29

What can lossy compression be used for?

Answer 29

Images and audio

Question 30

What does lossless compression do?

Answer 30

Represents the file in a more efficient way

Question 31

What can lossless compression be used for?

Answer 31

Text documents and program files